焊接电流对低密度钢焊接性能的影响

Effect of welding current on weldability of low density steel

为研究不同焊接电流对焊接低密度钢的金相组织、显微硬度、切应力及拉伸性能的影响,用200、190、185 A电流焊接低密度钢。结果表明:焊接电流越小,晶粒越细,对组织影响越大,热影响区晶粒增大;显微硬度最高处为熔合区,最低处为焊缝区;显微硬度随焊接电流增大先增后减;焊接电流为190 A时,切应力最大,为120 N,随结合宽度增大,切应力增大;焊接电流为190 A时焊后力学性能最好。

In order to study the effect of different welding currents on the microstructure,microhardness,shear stress and tensile properties of low density steel,currents of 200 A,190 A and 185 A were used to weld low density steel. The results show that the smaller the welding current is,the finer the grain is,the greater the influence of heat on the microstructure is,and the grain size in the heat affected area increases. The microhardness of fusion zone is highest,and the microhardness of weld zone is lowest. The microhardness firstly increases and then decreases with the increase of welding current. When the welding current is 190 A,the maximum shear stress is 120 N. With the increase of bonding width,the shear stress increases. When the welding current is 190 A,the mechanical properties are the best.